The present invention relates to an electric supercharger.
Japanese Patent Application Publication No. 2008-38869 discloses a multistage supercharging type exhaust turbocharger.
The above turbocharger has a high-pressure compressor cover that is formed as an integrated compressor cover incorporating therein a compressor inlet passage for intake air and a bypass inlet passage having an opening and closing part operated by the compressor bypass valve device.
In an internal combustion engine having a conventional supercharger of another structure. EGR gas, or part of gas exhausted from the internal combustion engine, is allowed to flow through an EGR device into an intake passage in which intake air flows upstream of the supercharger so that a mixture of the intake air and the EGR gas is compressed by the supercharger and supplied to the internal combustion engine. However, an internal combustion engine having such a supercharger has a problem in that the intake passage becomes large in size and it is difficult to install the EGR device in a vehicle because the joining portion of the EGR device is provided separately from the supercharger.
The present invention which has been made in light to the above problem is directed to providing an electric supercharger that is easily installed in a vehicle.